Responses
I believe it's Jaeyoung.
My theory is that he is obsessed with Jaeyoung and gave him the stage name Happy to him, and we could also see that Jun (the blonde psycho) is mentioned to be the one looking for Jaeyoung. Since the drug he used is also called happy like it is signifying for the blonde psycho that Jaeyoung is his drug, his happy. And looking at his text with Jaeyoung, I think his desire to protect him is more of the desire to keep Jaeyoung close to him.
Idk this is all my opinion when I read this.
I was smiling with our lovebirds, but it disappeared when I saw that blond psycho. Is the Happy guy he's trying to contact Seungmin? Considering they could both be connected through the drug stuff and rap¿¿ Or it's Jaeyoung? and I'm just dumb xd It just seemed strange to me that Jun's messages showed concern for Happy or a desire to 'protect' him when we know he's the one who messed with Jaeyoung ? And well, it confuses me to think that now, seriously, he flew all the way to Korea just to find out how he is and interfere in his life ;-;